Fades audibly, like colours (4)
I believe the answer is:
dyes
'colours' is the definition.
(dyeing is a kind of colouring)
'fades audibly like' is the wordplay.
I cannot really understand how this works, but
'like' could be 'y' (similar in meaning) and 'y' is found in the answer.
The remaining letters 'des' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for dyes that I've seen before include "Colour" , "turns green, possibly" , "Colouring materials" , "Stains" , "Many a pigment" .)